Water separator, fuel cell system and motor vehicle

Abstract

The technology disclosed herein relates to a water separator 10 for the exhaust gas path of a fuel cell, comprising an enclosed receiving chamber 20 and three connection elements 31, 32, 33 with openings 41, 42, 43, wherein the openings 41, 42, 43 are arranged vertically offset from one another. The technology disclosed herein further relates to a fuel cell system with such a water separator 10 and to a motor vehicle with such a fuel cell system.

Description

The technology disclosed herein relates to a water separator for the exhaust gas path of a fuel cell, a fuel cell system having such a water separator, and a motor vehicle having such a fuel cell system.Fuel cells are used in mobile or stationary devices to generate electrical energy from fuel such as hydrogen or methane. Since hot combustion processes are dispensed with in fuel cells and instead an electrochemical reaction of the fuel takes place, these typically do not generate any harmful exhaust gases. However, when using hydrogen as fuel, water is naturally obtained as product of the electrochemical process, for example, since the hydrogen reacts with oxygen to form water, thereby releasing energy.This water can be conducted into the environment, for example, through a suitable exhaust system. However, there may also be situations in which such a discharge into the environment is not possible or is not desired, for example because the water would lead to undesired cloud formations or a vehicle is used, for example, as a transport vehicle in interiors, where water could lead, for example, to a risk of slipping. For this case, water separators are used, wherein an exhaust gas of the fuel cell is first conducted into the water separator, where the water condenses out. Subsequently, an exhaust gas is conducted to the outside, from which the water has been substantially removed. The water is collected in the water separator and regularly drained, so that the fuel cell can continue to be operated.It is a preferred object of the technology disclosed herein to reduce or eliminate at least one disadvantage of a prior art solution or to propose an alternative solution. It is in particular a preferred object of the technology disclosed here to increase the safety when using a water separator. Further preferred objects may result from the advantageous effects of the technology disclosed herein. The objects are achieved by the subject matter of the independent claims. The dependent claims represent preferred embodiments.The technology disclosed here relates to a water separator for the exhaust gas path of a fuel cell, comprising (i) an enclosed receiving space, (ii) a first connection element having a first opening in the receiving space for introducing anode exhaust gas, (iii) a second connection element having a second opening in the receiving space for discharging gas, and (iv) a third connection element having a third opening in the receiving space for introducing cathode exhaust gas and / or dilution gas, wherein, at least in an operating orientation of the water separator, the first opening is arranged below the second opening and the second opening is arranged below the third opening.By means of such a water separator, it can be achieved in a particularly advantageous manner that, in the event of a water level in the water separator which is so high that at least one of the openings is no longer arranged above the water level, the openings are closed off when the water level is too high in a sequence in which the reliability of the operation of the fuel cell is impaired as little as possible. Thus, it is possible to provide for the case that the water level is higher than actually provided, for example because a discharge of water was forgotten or because more water was produced in a specific period of time due to unusual operation of the fuel cell than otherwise.The first opening introduces anode exhaust gas. If it is closed, this typically leads to an automatic shut-down of the fuel cell due to a back pressure. Typically, a safe state is already established as a result, since the fuel cell is switched off. If the water level nevertheless continues to rise, the second opening and the third opening initially remain open. In this case, it is furthermore ensured that cathode off-gas and / or dilution gas can penetrate further into the water separator through the third opening, with the result that any hydrogen still emerging and contained in the anode off-gas is diluted further and only enters the second opening in the diluted state, in order then to be discharged. Undiluted hydrogen discharge is avoided in this way.If the water level rises so high that the second opening also closes, the third opening still remains open at first, as a result of which cathode off-gas and / or dilution gas is fed further, so that any hydrogen still present is diluted further. In the embodiment of a water separator described herein, a possible closure of the three openings thus takes place exactly in the sequence in which it is optimum for the safety of the fuel cell.A water separator is understood in particular to mean a component which serves to separate off water contained in an exhaust gas stream. For this purpose, the exhaust gas stream is introduced into the water separator, which provides a separating and receiving space. There, the water condenses out and the exhaust gas stream is subsequently discharged again from the water separator. Typically, at least a portion or the predominant portion of the water contained in the exhaust gas stream condenses in the water separator. Typically, the water is collected in the water separator until it is drained. For this purpose, the water separator preferably has a drain valve for draining off water accumulated in the receiving space. This drain valve can be located, for example, on an underside of the water separator, in particular in the operating orientation. The receiving space is that space of the water separator in which the water is collected until it is drained or otherwise removed.A connection element is understood in particular to mean an element which establishes a fluidic connection from the receiving space to another unit. The first connection element serves for the introduction of anode off-gas. For this purpose, the connection element is suitably designed to be connected to that connection of a fuel cell from which anode off-gas is discharged. For example, this can be a purge valve. An anode path of the fuel cell is typically regularly vented via such a purge valve, wherein gaseous fuel such as hydrogen may typically also be contained in the anode exhaust gas. In this case, provision is typically made for the gaseous fuel to be diluted in order to avoid the formation of concentrations which may be ignited. For this purpose, the cathode off-gas, which originates from a cathode path of the fuel cell, is typically used. The cathode path of the fuel cell typically contains ambient air or oxygen to provide an oxidant to the fuel cell. For example, in an exhaust gas path without a water separator, the cathode exhaust gas could be mixed with the anode exhaust gas, so that any hydrogen contained in the anode exhaust gas is diluted by the cathode exhaust gas. This can also be done when using a water separator, wherein the use of the water separator described herein advantageously ensures that the dilution is not impaired even in the event of a water level being too high. The second connection element is preferably designed to be connected to an exhaust gas hose or another device for discharging exhaust gas into the ambient air. This allows exhaust gas to be discharged at an appropriate location on an automobile. The third connection element is typically designed to be connected to a connection of the fuel cell, at which cathode exhaust gas flows out. Alternatively or additionally to the use of cathode exhaust gas, it is also possible to feed special dilution gas, for example ambient air, which ensures that any hydrogen contained in the anode exhaust gas is diluted.The operating orientation of the water separator is typically that orientation which the water separator assumes in an installation situation in a motor vehicle, in particular when the motor vehicle is located on a planar underlying surface. This is therefore typically the situation which is usually assumed during the operation of the motor vehicle. Such an operating situation is typically also recognizable on a separate water separator, so that the vertical orientation of the openings is also recognizable. Unless otherwise indicated, references herein to orientation of operation are intended. The operating alignment can also be characterized in that the first opening, the second opening and / or the third opening have a maximum vertical distance from the lowermost point of the receiving space.According to an advantageous embodiment, the water separator has a first float valve which is designed to close the first opening or the first connection element from a first predetermined water level in the receiving space. According to an advantageous embodiment, the water separator has a second float valve which is designed to close the second opening or the second connection element from a second predefined water level in the receiving space. According to an advantageous embodiment, the water separator has a third float valve which is designed to close the third opening or the third connection element from a third predefined water level in the receiving space.A float valve is understood in particular to mean a valve which is actuated by means of a float. Such a float valve typically comprises a float. This is designed such that it floats on a water surface, in particular due to a sufficiently low density. The float is typically mechanically connected, for example by a lever, to the switching part of the valve. If the water level exceeds a predetermined water level, the float floats so high that the valve is actuated for closing via the mechanical connection. Alternatively, electronic detection of the position of the float and electronic actuation of the valve is also possible. In principle, it is alternatively also possible to electronically detect the water level without a float; this is considered to be equivalent. The float valve ensures in particular that closure is possible even more reliably, with the result that a fuel cell switches off even more reliably if the water level impairs reliable operation.The designation as first, second and third float valves serves only for the assignment to the three openings. Each of said float valves may or may not be present in an embodiment. Thus, for example, the third float valve may be present, although the first float valve is not present. The same applies to the buoyancy bodies described below.According to an advantageous embodiment, the water separator has a first buoyancy body which is mounted under the first opening such that it can move vertically and which is pressed against the first opening by a buoyancy force and closes it when a water level in the water separator is higher than the first opening. According to an advantageous embodiment, the water separator has a second buoyancy body which is mounted below the second opening such that it can move vertically and which is pressed against the second opening by a buoyancy force and closes it when a water level in the water separator is higher than the second opening. According to an advantageous embodiment, the water separator has a third buoyancy body which is mounted below the third opening such that it can move vertically and which is pressed against the third opening by a buoyancy force and closes it when a water level in the water separator is higher than the third opening.A better closure can also be achieved by such buoyancy elements than purely by using the hydrostatic pressure above the opening.A float may in particular have a cavity of at least 50 cm 3, at least 100 cm 3, at least 150 cm 3, at least 200 cm 3, at least 500 cm 3 or of at least 1,000 cm 3. It may also have a cavity of at most 150 cm 3, at most 200 cm 3, at most 500 cm 3 or at most 1,000 cm 3. From each lower limit and each larger upper limit, an appropriate interval may be formed. For example, it may have a cavity of 160 cm 3. This ensures that even for easy immersion of the opening into the water present, a reliable closure of the opening against typical pressures used when discharging gas from a fuel cell takes place.According to one embodiment, the receiving space has a first region and a second region, wherein the first region is arranged above the second region in the operating orientation, wherein the first region has a smaller horizontal cross-sectional area in the operating orientation than the second region, and wherein the first opening, the second opening and the third opening are arranged in the first region. By means of such an embodiment, the second region is first made available as an extensive water reservoir with a large cross-sectional area and thus a large volume. Water can collect in this without any effect on the openings. If the water level increases to such an extent that it extends into the first region, the water level subsequently increases more quickly, so that provision is also made for a more rapid closing of the openings. As a result, the already mentioned safety functionalities can be realized more quickly.In particular, the first region at each location along a vertical axis can have a smaller cross-sectional area than the second region at each location along the vertical axis. This can be realized, for example, in such a way that the second region is designed as a, for example, cuboidal tank, from which the first region projects upward as a tube with a thinner cross section. For example, a maximum cross-sectional area of the first region may be at most 50%, at most 20% or at most 10% of a maximum cross-sectional area of the second region. The first region can have a constant cross section, for example. Likewise, the second region can have a constant cross section, for example. However, different cross sections are also possible.According to one embodiment, the receiving space has a constant horizontal cross section in the operating orientation. This allows a simple embodiment, wherein a water level typically increases continuously with uniform separation of water over time. The constant cross section can be present in particular along a vertical axis in the operating orientation.In principle, other forms than those described are also possible.For example, in the operating orientation, the first opening may be at least 1 cm vertically spaced from the second opening. Furthermore, for example, in the operating orientation, the second opening can have a vertical distance of at least 1 cm from the third opening. This makes it possible to ensure that the openings actually close one after the other, even if, for example, the water should slosh due to travel movements.According to one embodiment, the first connection element is formed completely, or at least directly adjacent to the first opening, as a straight tube. According to one embodiment, the second connection element is formed completely, or at least directly adjacent to the second opening, as a straight tube. According to one embodiment, the third connection element is formed completely, or at least directly adjacent to the third opening, as a straight tube. Such an embodiment as a straight tube achieves a simple realization of the connection elements. On the top side, a connecting line to the fuel cell and / or to a further exhaust gas path can be connected to the pipe. On the bottom side, the opening is located on the tube, which is arranged in the receiving space.According to one embodiment, the first connection element is oriented vertically in the operating orientation completely, or at least directly adjacent to the first opening. According to one embodiment, the second connection element is oriented vertically in the operating orientation completely, or at least directly adjacent to the second opening. According to one embodiment, the third connection element is oriented vertically in the operating orientation completely, or at least directly adjacent to the third opening. This allows the gases to be supplied and discharged from above, so that no consideration has to be taken of effects which may possibly arise from unusual routing and crossing of the water level. In addition, water is prevented from penetrating into the connection elements.The technology disclosed herein further relates to a fuel cell system comprising (i) a fuel cell having a cathode exhaust port and an anode exhaust port, and (ii) a water separator as described herein, wherein the cathode exhaust port is connected to the third terminal element and wherein the anode exhaust port is connected to the first terminal element. By means of such a fuel cell system, the advantages of a water separator for a fuel cell system already mentioned above can be realized. In particular, safety is thereby increased. The fuel cell system may further include an exhaust pipe connected to the second connector.The technology disclosed herein further relates to a motor vehicle having a fuel cell system as described herein. With regard to the fuel cell system and in particular the water separator contained therein, all embodiments and variants described herein can be used. In particular, the water separator can be oriented in the operating orientation when the motor vehicle is standing on a flat surface. This allows typical operation of the water separator as described above in a normal operating mode.The fuel cell already mentioned can be configured in particular to convert the chemical energy of the fuel into other energy forms, for example into electrical energy and / or into kinetic energy. The fuel cell system described herein can be intended in particular for mobile applications such as motor vehicles (for example passenger cars, bicycles, commercial vehicles), in particular for providing the energy for at least one drive machine for the movement of the motor vehicle. In its simplest form, a fuel cell is an electrochemical energy converter that converts fuel (e.g., hydrogen) and oxidant (e.g., air, oxygen, and peroxides) into reaction products, thereby producing electricity and heat.A fuel cell system typically includes an anode subsystem formed by the fuel carrying components of the fuel cell system. An anode subsystem may include at least one pressure vessel, at least one tank shut-off valve, at least one pressure reducer, at least one anode supply path leading to the anode inlet of the fuel cell stack, an anode space in the fuel cell stack, at least one recirculation supply path leading away from the anode outlet of the fuel cell stack, at least one anode purge valve, at least one active or passive fuel recirculation conveyor, and further elements. The main task of the anode subsystem is the supply and distribution of fuel to the electrochemically active surfaces of the anode compartment and the discharge of anode off-gas. Anode off-gas of this type can be conducted into the water separator as already described above.The fuel cell system typically includes a cathode subsystem. The cathode subsystem is formed from the oxidizer-carrying devices. A cathode subsystem may include at least one oxidant conveyor, at least one cathode supply path leading to the cathode inlet, at least one cathode exhaust gas path leading away from the cathode outlet, a cathode space in the fuel cell stack, and other elements. The main task of the cathode subsystem is the supply and distribution of oxidizing agent to the electrochemically active surfaces of the cathode chamber and the discharge of unused oxidizing agent.The water separator described herein is provided in particular for being arranged in an exhaust gas path of the fuel cell system. A water separator is in particular a technical device for separating water from gas mixtures, aerosols or suspensions. Different designs and functional principles can be used here. Preferably, a liquid water separator with flow diversion through separating surfaces is used. The exhaust gas path is typically the path which is arranged downstream of the anode outlet or the cathode outlet of the fuel cell stack. The exhaust gas path can open directly or indirectly into the environment and / or be a recirculating path (dead-end system).In other words, hydrogen fuel cell systems are basically known. It is known that such systems "purge" small amounts of hydrogen into the environment due to operation. It is also known that these hydrogen quantities are diluted to an non-critical quantity by the cathode exhaust gas before they leave the system (safety function). Water separators can be used, for example, in certain applications such as industrial vehicles or airport apron vehicles by condensing out and storing product water (from anode and cathode) in order not to have to discharge the product water into the environment during operation. The product water is collected in the separator in order to be disposed of (in particular discharged or pumped off) at a special discharge point (for example filling station). Since water also accumulates on the anode side of the fuel cell, the anode purge gas and the anode drain water are also directed into the water separator. The water separator therefore has the function, among other things, of collecting the "purge" gas and the "drain" water, mixing them with the cathode exhaust gas to an non-critical concentration, thereby condensing out and switching off the water contained.Due to the function, the water level in the water separator increases during the operation of the fuel cell system. In very rare cases, depending on the position and position of the water separator, it may occur that the water blocks the feed openings. If the blockage concerns the supply of the cathode off-gas, the dilution functionality already described further above can be impaired. In order to increase safety, a special construction for the supply line into the water separator is therefore proposed herein. In this case, the feed lines into the water separator are to be designed by means of different inlet lengths such that the introduction of the "purge" and "drain" gas by the water and its hydrostatic pressure in the separator is first blocked. After this, it should be possible for the exhaust air line to be blocked first and for the cathode exhaust gas to be blocked last. In order to be able to implement this function, the water separator can also be geometrically adapted. Thus, for example, a geometry which has a high volume and a low hydrostatic pressure in the lower region and a lower volume with a high hydrostatic pressure in the upper region, i.e. during overflow, would be suitable for this functionality. In a further embodiment, the inlet and outlet air lines can be shut off by valves or buoyancy elements at different water levels in the water separator. Float valves can be used for this purpose, for example. The blockage or blocking hinders the operation of the fuel cell in such a way that it switches off.The proposed simple and fail-safe construction prevents the discharge of undiluted hydrogen into the environment. The proposed construction has a high integrity due to the constructional characteristics by introduction or use of a float valve or float body. A float switch which switches off the fuel cell directly in response to a high water level can be saved in this way. However, it can also be additionally present.The technology disclosed herein will now be described with reference to the figures.The following are shown: FIG. 1 : a water separator according to a first exemplary embodiment, FIG. 2 : a water separator according to a second exemplary embodiment, and FIG. 3 : shows a water separator according to a third exemplary embodiment.FIG. 1 shows a water separator 10 for the exhaust gas path of a fuel cell, not shown. The water separator 10 has a receiving space 20. The receiving space 20 is designed to receive water which is separated from an exhaust gas flow of a fuel cell. Such water is typically present in such an exhaust gas flow, since it naturally arises during the electrochemical process which takes place in a fuel cell.In the embodiment of FIG. 1, the receiving space 20 is divided into a first region 21 and a second region 22. The first region 21 is arranged above the second region 22. As shown, the first region 21 has a significantly smaller horizontal cross-sectional area than the second region 22, which, like the embodiment shown otherwise, relates to an operating orientation which corresponds to a typical installation state of the water separator 10 in a motor vehicle when the motor vehicle is standing on a planar horizontal base.In the present case, a water level 15 is shown up to which the receiving space 20 is filled with water. The water level 15 basically depends on how much water has accumulated in the receiving space 20. By suitable draining or pumping down, the water level 15 can be lowered. First, the second region 22 provides a large space in which separated water can be stored. As long as this is not drained, the water level 15 rises further and further. If it rises so high that it penetrates into the first region 21, it rises more quickly with the same separation rate of water.The water separator 10 has a first connection element 31 for introducing anode exhaust gas. This first connection element 31 is thus connected in particular to an anode exhaust gas connection of a fuel cell. The water separator 10 has a second connection element 32, which is provided for discharging gas. Thus, gas can be discharged from the receiving space 20 and supplied to an exhaust line through which the gas can be discharged into the environment. Furthermore, the water separator 10 has a third connection element 33, which is designed for introducing cathode exhaust gas and / or dilution gas. This can be connected in particular to a cathode exhaust gas connection of a fuel cell and / or to a source of dilution gas, for example a blower suitable for this purpose. The three connection elements 31, 32, 33 are vertically oriented as shown. This corresponds to a simple embodiment, other embodiments also being possible. The first connection element 31 has a first opening 41 on the bottom side. The second connection element 32 has a second opening 42 on the bottom side. The third connection element 33 has a third opening 43 on the bottom side. The openings 41, 42, 43 are each arranged on the bottom side of the tubular connecting elements 31, 32, 33.If the water level 15 rises so high that it meets the first opening 41, the first opening 41 is closed. This makes it more difficult for anode off-gas to escape or even to prevent it under sufficient pressure. In typical designs of fuel cells, this leads to the fact that further discharge of anode off-gas is no longer possible, which is detected by control electronics of the fuel cell and leads to the fuel cell being switched off. Although this represents an impairment of the operation, it provides a distinct increase in safety in the case in question in which reliable operation of the water separator 10 is no longer possible. In principle, however, the functionality of diluting exhaust gas discharged from the second connection element 32 is initially maintained, since the second opening 42 and the third opening 43 are still open.If the water level 15 rises further, it also closes the second opening 42 at a corresponding height. This also typically leads to a connected fuel cell being switched off, so that this also contributes to increasing safety.If the water level 15 rises even further, it also closes the third opening 43. This also typically triggers safety functions in a fuel cell, which lead to their switching off.Overall, the described embodiment thus achieves that a closure of openings 41, 42, 43, if this is unavoidable on account of an excessively high water level, for example because a discharge of water has been forgotten, takes place in the sequence in which the best possible influence on the safety of the operation of the fuel cell is ensured.FIG. 2 shows a water separator 10 according to a second exemplary embodiment. In contrast to the first exemplary embodiment, the receiving space 20 is formed with a constant horizontal cross section, the subdivision into the first region 21 and the second region 22 being dispensed with. In principle, however, such a subdivision as is shown in FIG. 1 would also be possible in the embodiments of FIGS. 2 and 3. Flow directions of gases are represented by arrows in FIG. 2 and also in FIG. 3.In the embodiment of FIG. 2, a float valve 50 is formed in the first connection element 31. This has a float 60 and a lever 65 connected thereto. The float valve 50 is a shut-off valve which is basically capable of shutting off the first connection element 31 when the float 60 is raised above a certain level due to the water level 15. As a result, a closure is achieved not only by the first opening 41 being immersed in the water contained on account of hydrostatic pressure, but additionally also by a mechanical actuation of the float valve 50.FIG. 3 shows a water separator 10 according to a third exemplary embodiment. In contrast to the second exemplary embodiment, a float 55 is arranged directly below the first opening 41 so as to be vertically movable. The float has a hollow space on the inside. Thus, it floats up at a corresponding water level 15 and is pressed directly against the first opening 41 due to the buoyancy force acting on it, whereby it closes the latter. Components outside the receiving space 20 for achieving valve functionality can thus be advantageously dispensed with.The described valve or float functionalities can additionally or alternatively also be provided for the second connection element 32 and the third connection element 33. This also allows for an improved shut-off in these connection elements 32, 33 when the water level 14 reaches a certain level, so that not only the hydrostatic pressure has to ensure a closure of the respective opening 41, 42, 43.For the sake of convenience, the term "at least one(s)" has been partly omitted for convenience. If a feature of the technology disclosed here is described in singular or indefinite (e.g. the / one receiving space, the / one lever, etc.), the plurality thereof should also be disclosed simultaneously (e.g. the at least one receiving space, the at least one lever, etc.).The foregoing description of the present invention is for illustrative purposes only and is not intended to limit the invention. Various changes and modifications are possible within the scope of the invention without departing from the scope of the invention and its equivalents.List of reference characters10 Water separator 15 Water level 20 Receiving space 21 First region 22 Second region 31 First connection element 32 Second connection element 33 Third connection element 41 First opening 42 Second opening 43 Third opening 50 Float valve 55 Float 60 Float 65 Lever

Claims

Water separator (10) for the exhaust gas path of a fuel cell, comprising - an enclosed receiving space (20), - a first connection element (31) with a first opening (41) in the receiving space (20) for introducing anode exhaust gas, - a second connection element (32) with a second opening (42) in the receiving space (20) for discharging gas, and - a third connection element (33) with a third opening (43) in the receiving space (20) for introducing cathode exhaust gas and / or dilution gas, wherein at least in an operating orientation of the water separator (10) the first opening (41) is arranged below the second opening (42) and the second opening (42) is arranged below the third opening (43).Water separator (10) according to claim 1, further comprising - a first float valve (50) configured to close the first opening (41) or the first connection element (31) from a first predetermined water level in the receiving space (20), and / or - a second float valve configured to close the second opening (42) or the second connection element (32) from a second predetermined water level in the receiving space (20), and / or - a third float valve configured to close the third opening (43) or the third connection element (33) from a third predetermined water level in the receiving space (20).Water separator (10) according to claim 1 or 2, further comprising - a first buoyancy body (55) which is mounted vertically movably below the first opening (41) and which is pressed against and closes the first opening (41) by a buoyancy force when a water level (15) in the water separator (10) is higher than the first opening (41), and / or - a second buoyancy body which is mounted vertically movably below the second opening (42) and which is pressed against and closes the second opening (42) by a buoyancy force when a water level (15) in the water separator (10) is higher than the second opening (42), and / or - a third buoyancy body which is mounted vertically movably below the third opening (43) and which is pressed against and closes the third opening (43) by a buoyancy force, if a water level (15) in the water separator (10) is higher than the third opening (43).Water separator (10) according to any one of the preceding claims, wherein the receiving space (20) comprises a first region (21) and a second region (22), wherein the first region (21) is arranged above the second region (22) in the operating orientation, wherein the first region (21) has a smaller horizontal cross-sectional area in the operating orientation than the second region (22), and wherein the first opening (41), the second opening (42) and the third opening (43) are arranged in the first region.The water separator (10) of claim 4, wherein in the operational orientation the first region (21) at each location along a vertical axis has a smaller cross-sectional area than the second region (22) at each location along the vertical axis.Water separator (10) according to claim 4 or 5, wherein a maximum cross-sectional area of the first region (21) is at most 50%, at most 20% or at most 10% of a maximum cross-sectional area of the second region (22).Water separator (10) according to any one of claims 4 to 6, wherein the first region (21) has a constant cross section and / or wherein the second region (22) has a constant cross section.Water separator (10) according to any one of claims 1 to 3, wherein the receiving space (20) has a constant horizontal cross section in the operating orientation.Water separator (10) according to any one of the preceding claims, - wherein in the operating orientation the first opening (41) has a vertical distance of at least 1 cm from the second opening (42), and / or - wherein in the operating orientation the second opening (42) has a vertical distance of at least 1 cm from the third opening (43).Water separator (10) according to one of the preceding claims, - wherein the first connection element (31) is designed as a straight pipe completely or at least directly adjacent to the first opening (41), and / or - wherein the second connection element (32) is designed as a straight pipe completely or at least directly adjacent to the second opening (42), and / or - wherein the third connection element (33) is designed as a straight pipe completely or at least directly adjacent to the third opening (43).Water separator (10) according to one of the preceding claims, - wherein the first connection element (31) is oriented vertically in the operating orientation completely, or at least directly adjacent to the first opening (41), and / or - wherein the second connection element (32) is oriented vertically in the operating orientation completely, or at least directly adjacent to the second opening (42), and / or - wherein the third connection element (33) is oriented vertically in the operating orientation completely, or at least directly adjacent to the third opening (43).Fuel cell system, comprising - a fuel cell having a cathode exhaust gas connection and an anode exhaust gas connection, and - a water separator (10) according to one of the preceding claims, wherein the cathode exhaust gas connection is connected to the third connection element (33) and wherein the anode exhaust gas connection is connected to the first connection element (31).The fuel cell system of claim 12, further comprising an exhaust pipe connected to the second connector (32).A motor vehicle comprising a fuel cell system according to claim 12 or 13.The motor vehicle of claim 14, wherein the water separator (10) is oriented in operational alignment when the motor vehicle is standing on a planar surface.

Images